PUPILS as young as five will sit three tests each lasting up to an hour long under controversial proposals being considered by ministers.

Parents have warned that Scottish Government plans for standardised national testing in primary and secondary schools currently include assessments for literacy, spelling and numeracy of up to 60 minutes in length.

The National Parent Forum of Scotland said the proposals for pupils in P1, P4, P7 and S3 were far in excess of what was acceptable and would lead to increased stress - even if the tests were split into smaller segments to make them more manageable.

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However, the Scottish Government said no primary pupil would be expected to take a test lasting an hour in length at one sitting and insisted the impact on children would be monitored closely.

The intervention from the forum is unprecedented because, until now, it has been broadly supportive of SNP testing plans despite opposition from teaching unions.

It comes just weeks after thousands of parents in England took their children out of school for a day in protest at new national tests there.

Iain Ellis, chair of the forum, said: "Our original understanding was that pupils would sit one short test reflecting different skills over a period of about twenty minutes and that the results of that test would be used to support the judgement of the teacher as to the level the pupil had achieved.

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"What we are now seeing is that these tests are numerous and lasting up to an hour each and that would put far too much pressure and stress on the individual pupils, particularly those in the first year of primary, but also those in secondary who would already be preparing for National qualifications.

"When you make the tests this numerous and lasting this long then that is no longer in the best interests of pupils and is more about an agenda to collect data for use at a national level and that is a very dangerous position to be in."

Mr Ellis said one scenario was that the hour-long tests would be split up into a number of sections - but said that would make the problem of teaching to the test even more acute because the school year would be dominated by a succession of tests.

"That would be even worse because, rather than just doing one short test, teachers would be preparing pupils for test after test and that would dominate the classroom agenda," he added.

"I’m not even sure whether primary schools could actually cope with that amount of additional workload given everything else they are delivering."

Last year, First Minister Nicola Sturgeon announced that standardised testing for primary and secondary pupils was to be introduced for all pupils at key stages of their school career.

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The move came after the biennial Scottish Survey of Literacy found standards of reading and writing were falling despite the introduction of the Curriculum for Excellence, which was expected to raise basic standards.

Ms Sturgeon said the tests would provide a better picture of how schools across Scotland were performing which would help close the attainment gap between rich and poor.

New Education Secretary John Swinney said: "No child at primary school will sit an hour-long test. Ministers have no wish to return to stressful testing in Scotland's schools for our children.

"We are introducing assessments, which will be age appropriate, and will allow teachers to tailor learning for each individual child." 

A Scottish Government spokeswoman added: "Standardised assessments should not be confused with national testing.

"We will ensure that the impact on children of any new assessments is monitored closely. Nearly all schools in Scotland are already using standardised assessments and the intention is to replace these with assessments aligned to Curriculum for Excellence.”

In 2003, the former Labour-led Scottish Executive scrapped national testing because of the concern teachers had become overly-focused on "teaching to the test" rather than educating pupils.

As a result, the national survey of five to 14 attainment, which tested every pupil in primary school and the first two years of secondary school, was replaced by a system of scientific sampling to track the performance of a proportion of pupils.

The majority of Scotland's local authorities still use some form of standardised assessment to judge pupils' progress, but because they use different systems building a national picture of attainment is difficult.

Standardised testing is controversial because opponents believe it allows league tables to be drawn up which directly compare schools serving completely different communities.